/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.table.descriptors

/**
  * A trait that adds a set of string-based, normalized properties for describing DDL information.
  *
  * Typical characteristics of a descriptor are:
  * - descriptors have a default constructor and a default 'apply()' method for Scala
  * - descriptors themselves contain very little logic
  * - corresponding validators validate the correctness (goal: have a single point of validation)
  */
trait Descriptor {

  /**
    * Internal method for properties conversion.
    */
  private[flink] def addProperties(properties: DescriptorProperties): Unit

  override def toString: String = {
    val descriptorProperties = new DescriptorProperties()
    addProperties(descriptorProperties)
    descriptorProperties.toString
  }
}
